There is a need for multiplexed assay technologies that enable diagnostics and detailed characterization of rheumatoid arthritis. In this project we plan to discover new rheumatoid arthritis biomarkers and implement them in a panel of multiplexed assays. We propose a novel approach that offers significant advances over existing methods, including the ability to rapidly develop, validate, and implement highly multiplexed, high- performance assays. If successful, our long-term goal is to transfer these new assays to the clinic as valuable new tools for high sensitivity diagnostics and treatment decision- making.